I love my 3ware raid controllers, the application I use isĀ tw_cli. but getting the serials is a bit a hidden given; you should explicitly ask the raid controller for the serial. This can be done with :

tw_cli /c0/p1 show serial

Since we are lazy, we only type it once and profit !

for i in {8..15}; do tw_cli /c0/p$i show serial; done